Skeletal stability following mandibular advancement with and without advancement genioplasty.

The correction of most cases of skeletal class II mandibular deficiency requires surgical advancement of the mandible for treatment of the malocclusion. Often genioplasty is included in the procedure to improve the soft tissue profile. Long-term skeletal stability is an important goal for the surgeon and orthodontist following bilateral sagittal split osteotomy (BSSO) and is influenced by the muscles attached to the mandible. Following the surgical advancement of the mandible, the suprahyoid muscle complex is stretched and even more so when the procedure is combined with surgical advancement of the chin. This retrospective comparative study determined the long-term skeletal stability of patients who had undergone surgical advancement of the mandible by means of BSSO with an advancement genioplasty, compared to those who had undergone mandibular advancement surgery (BSSO) without an advancement genioplasty. This study concluded that the postoperative hard tissue relapse following BSSO advancement, with or without genioplasty, was clinically insignificant.

Emotional adjustment over 1 year post-diagnosis in patients with cancer: understanding and predicting adjustment trajectories.

PURPOSE: The aim of this study was to determine the prevalence of basic trajectories in emotional adjustment in cancer survivors and identify predictors of long-term change. METHODS: We assessed 421 patients with cancer after diagnosis and 6 and 12 months later. Measures comprised anxiety, depression, perceived support, desired support, and illness intrusiveness. RESULTS: Anxiety decreased over time, whereas depression increased as did need for support. About one third of initial diagnostic classifications (into low distress, symptoms, or clinical level of distress) changed from one assessment to the next. Lower age and higher illness intrusiveness predicted which patient showed worse adjustment over time. CONCLUSION: To avoid both over- and undertreatment of distressed individuals, repeated measurements are needed to identify actual adjustment trajectories. Initial assessment of emotional reaction to a diagnosis is not a reliable predictor of long-term adjustment. Patients should be made aware that completion of initial medical treatment even when accompanied by a positive prognosis does not in and of itself forecast how well patients adjust during survivorship.

Measuring symptoms in localized prostate cancer: a systematic review of assessment instruments.

It is critical for prostate cancer researchers and clinicians to have access to comprehensive, sensitive and simple-to-use symptom measures that allow them to understand and quantify the subjective patient experience. The purpose of the current review is to provide a comprehensive review, detailed tool descriptions and objectively defined quality criteria to facilitate tool choices for patients with localized prostate cancer. Using a systematic web-based literature search, we found n=29 prostate symptom measures described in n=35 validation studies. To be recommended, tools needed to meet four criteria: broad domain coverage, ability to differentiate objective and subjective experience, good internal consistency and validation in at least two populations and/or having achieved two types of validations. Of the 29 tools reviewed, n=7 meet our criteria for recommendation, and three in particular (the EPIC-26 (Expanded Prostate Cancer Index Composite)-26, PC-QOL (Prostate Cancer-Quality of Life) and the UCLA-PCI (UCLA Prostate Cancer Index)) showed the strongest psychometrics. There is a reasonable number of measures to choose from that meet criteria for good psychometrics.

A sensitivity analysis of a personalized pulse wave propagation model for arteriovenous fistula surgery. Part A: Identification of most influential model parameters.

Previously, a pulse wave propagation model was developed that has potential in supporting decision-making in arteriovenous fistula (AVF) surgery for hemodialysis. To adapt the wave propagation model to personalized conditions, patient-specific input parameters should be available. In clinics, the number of measurable input parameters is limited which results in sparse datasets. In addition, patient data are compromised with uncertainty. These uncertain and incomplete input datasets will result in model output uncertainties. By means of a sensitivity analysis the propagation of input uncertainties into output uncertainty can be studied which can give directions for input measurement improvement. In this study, a computational framework has been developed to perform such a sensitivity analysis with a variance-based method and Monte Carlo simulations. The framework was used to determine the influential parameters of our pulse wave propagation model applied to AVF surgery, with respect to parameter prioritization and parameter fixing. With this we were able to determine the model parameters that have the largest influence on the predicted mean brachial flow and systolic radial artery pressure after AVF surgery. Of all 73 parameters 51 could be fixed within their measurement uncertainty interval without significantly influencing the output, while 16 parameters importantly influence the output uncertainty. Measurement accuracy improvement should thus focus on these 16 influential parameters. The most rewarding are measurement improvements of the following parameters: the mean aortic flow, the aortic windkessel resistance, the parameters associated with the smallest arterial or venous diameters of the AVF in- and outflow tract and the radial artery windkessel compliance.

A sensitivity analysis of a personalized pulse wave propagation model for arteriovenous fistula surgery. Part B: Identification of possible generic model parameters.

Decision-making in vascular access surgery for hemodialysis can be supported by a pulse wave propagation model that is able to simulate pressure and flow changes induced by the creation of a vascular access. To personalize such a model, patient-specific input parameters should be chosen. However, the number of input parameters that can be measured in clinical routine is limited. Besides, patient data are compromised with uncertainty. Incomplete and uncertain input data will result in uncertainties in model predictions. In part A, we analyzed how the measurement uncertainty in the input propagates to the model output by means of a sensitivity analysis. Of all 73 input parameters, 16 parameters were identified to be worthwhile to measure more accurately and 51 could be fixed within their measurement uncertainty range, but these latter parameters still needed to be measured. Here, we present a methodology for assessing the model input parameters that can be taken constant and therefore do not need to be measured. In addition, a method to determine the value of this parameter is presented. For the pulse wave propagation model applied to vascular access surgery, six patient-specific datasets were analyzed and it was found that 47 out of 73 parameters can be fixed on a generic value. These model parameters are not important for personalization of the wave propagation model. Furthermore, we were able to determine a generic value for 37 of the 47 fixable model parameters.

Disease stage predicts post-diagnosis anxiety and depression only in some types of cancer.

BACKGROUND: We hypothesised that patients with advanced disease or a cancer type that has a poor prognosis may be more likely to report anxiety and depressive symptoms after diagnosis; younger age and female gender may moderate these effects. METHODS: Patients (n=3850) were consecutively assessed with PSSCAN, a standardised, validated tool, at two large cancer centres between 2004 and 2009. RESULTS: Female patients reported more anxiety and depressive symptoms (P=0.003 to P<0.001) compared with men and a healthy comparison group. Older age was associated with fewer anxiety (P=0.033 to P<0.001) and fewer depressive symptoms (P<0.001), but this was not true for lung cancer. Presence of metastases was associated with more anxiety symptoms in patients with gastrointestinal (P=0.044; R(2)Δ=0.001), lung (P=0.011; R(2)Δ=0.016), and prostate (P=0.032; R(2)Δ=0.008) cancer, but this was not true for breast cancer. Furthermore, early disease stage was associated with fewer depressive symptoms among older prostate cancer patients (P=0.021; R(2)Δ=0.008). Men with early lung cancer reported fewer anxiety (P=0.020; R(2)Δ=0.013) and depressive (P=0.017; R(2)Δ=0.016) symptoms than men with advanced disease or women. CONCLUSION: As hypothesised, disease stage was directly associated with emotional distress, except for patients with breast cancer. Furthermore, age and gender moderated some of these effects.

Measurement reliability for acupoint activity determined with the prognos ohmmeter.

The concepts of meridians and acupoints are critical to traditional Chinese medicine but are met with skepticism in Western medicine. Empirical validation of these concepts is in its beginning stages and still hampered by problems with measurement. A promising avenue and foundation for validity testing is the demonstration that acupoint activity can be reliably measured via determination of electrical resistance at well-defined body surface points. In this article, efforts are described to maximize measurement reliability; we tested a variety of protocols to determine which method of data aggregation is associated with maximal reliability. Twenty-one healthy individuals were subjected to 5 repeated measurement cycles to test the predicted increase in reliability with increasing number of aggregated measurements. Reliability, defined as internal consistency, was indeed highest for 5 measurements (mean alpha = .88). Even the aggregate of only three measures was quite reliable (alpha = .84). Reliability for measuring acupoints on the left side of the body was roughly .05 higher than on the right side. Consistent with previous literature, we conclude that with repeated measures the reliability of electrical resistance measurements at acupoints is high and that a strong foundation for validation research is now laid.

A Multivariate Multilevel Approach to the Modeling of Accuracy and Speed of Test Takers.

Response times on test items are easily collected in modern computerized testing. When collecting both (binary) responses and (continuous) response times on test items, it is possible to measure the accuracy and speed of test takers. To study the relationships between these two constructs, the model is extended with a multivariate multilevel regression structure which allows the incorporation of covariates to explain the variance in speed and accuracy between individuals and groups of test takers. A Bayesian approach with Markov chain Monte Carlo (MCMC) computation enables straightforward estimation of all model parameters. Model-specific implementations of a Bayes factor (BF) and deviance information criterium (DIC) for model selection are proposed which are easily calculated as byproducts of the MCMC computation. Both results from simulation studies and real-data examples are given to illustrate several novel analyses possible with this modeling framework.

A Box-Cox normal model for response times.

The log-transform has been a convenient choice in response time modelling on test items. However, motivated by a dataset of the Medical College Admission Test where the lognormal model violated the normality assumption, the possibilities of the broader class of Box-Cox transformations for response time modelling are investigated. After an introduction and an outline of a broader framework for analysing responses and response times simultaneously, the performance of a Box-Cox normal model for describing response times is investigated using simulation studies and a real data example. A transformation-invariant implementation of the deviance information criterium (DIC) is developed that allows for comparing model fit between models with different transformation parameters. Showing an enhanced description of the shape of the response time distributions, its application in an educational measurement context is discussed at length.

[How calcification in the atherosclerotic aorta can be associated with both a lower risk of recurrent stroke in clinical studies and an increased number of strokes in an autopsy study: interpretation based on selection bias]. / Hoe calcificatie in de atherosclerotische aorta kan samengaan zowel met minder recidiefherseninfarcten in klinisch onderzoek als met een toegenomen aantal herseninfarcten in obductieonderzoek: interpretatie op basis van selectiebias.

Studies evaluating the role ofcalcification in the relationship between aortic atherosclerosis and stroke have led to contradictory conclusions: clinical studies show that aortic calcification is linked to a reduced risk of recurrence in stroke patients, while an autopsy series found a positive association between aortic calcification and stroke. The controversy can be explained by assuming that the risk associated with aortic atherosclerosis varies among individuals. Low-risk patients would live longer and have more time to develop calcification. Consequently, calcification would be a sign of low risk. This explains the apparent recurrence-reducing effect of calcification in stroke patients. The association between aortic calcification and stroke found in an autopsy series does not contradict this hypothesis but supports it: application of Berkson's fallacy shows that calcification is linked to lower mortality.

Getting the most out of cardiac rehabilitation: a review of referral and adherence predictors.

Comprehensive cardiac rehabilitation reduces mortality and morbidity but is utilised by only a fraction of eligible cardiac patients, with the participation rate of women being only about half that of men. This quantitative review assesses 32 studies meeting inclusion criteria, describing 16,804 patients, 5882 of whom were female. It was found that the main predictor of referral to a cardiac rehabilitation programme was the physician's endorsement of the effectiveness of such a programme. Patients were more likely to participate in rehabilitation programmes when they were actively referred, educated, married, possessed high self efficacy, and when the programmes were easily accessible. Patients were less likely to participate when they had to travel long distances to participate in a cardiac rehabilitation programme, or experienced guilt over family obligations. Women were less often referred and participated less often even after referral. In conclusion, many of the observed predictors, including those particular to women, are potentially modifiable with the help of health professionals.

Dislocation of the mandibular condyle into the middle cranial fossa: report of a case with 5 year CT follow-up.

A 17-year-old patient suffered a dislocation of the right mandibular condyle into the middle cranial fossa following a motorcycle accident. Reduction was delayed because of serious orthopaedic injuries. The condyle was relocated into the glenoid fossa through a combined neurosurgical and preauricular approach. Five years later the patient presented for removal of wisdom teeth and a CT-scan was done to determine the effects of the trauma and management to the condyle. A fibro-osseous ankylosis had occurred in the right temporomandibular joint. The radiological changes confirm that early management appears to improve the prognosis for these injuries.

Analysis of multicomponent mass spectra applying Bayesian probability theory.

In this paper we develop a method for the decomposition of mass spectra of gas mixtures, together with the relevant calibration measurements. The method is based on Bayesian probability theory. Given a set of spectra, the algorithm returns the relative concentrations and the associated margin of confidence for each component of the mixture. In addition to the concentrations, such a data set enables the derivation of improved values of the cracking coefficients of all contributing species, even for those components for which the set does not contain a calibration measurement. This latter feature also allows one to analyze mixtures that contain radicals in addition to stable molecules. As an example, we analyze and discuss the mass spectra obtained from the pyrolysis of azomethane, which contain the radical CH3 apart from nitrogen and C1- and C2-hydrocarbons.

Simulations on infinite-size lattices.

We introduce a Monte Carlo method, as a modification of existing cluster algorithms, which allows simulations directly on systems of infinite size, and for quantum models also at beta = infinity. All two-point functions can be obtained, including dynamical information. When the number of iterations is increased, correlation functions at larger distances become available. Limits q-->0 and omega-->0 can be approached directly. As examples we calculate spectra for the d = 2 Ising model and for Heisenberg quantum spin ladders with two and four legs.

Individualized stress management for primary hypertension: a randomized trial.

OBJECTIVE: To test the efficacy of individualized stress management for primary hypertension in a randomized clinical trial with the use of ambulatory blood pressure (BP) measures. METHODS: Men and women aged 28 to 75 years with mean ambulatory BP greater than 140/90 mm Hg received 10 hours of individualized stress management by means of semistandardized treatment components. They were randomly assigned to immediate treatment (n = 27) or a wait list control group (n = 33). Participants on the wait list were subsequently offered treatment. Six-month follow-up data were available from 36 of the 45 participants who completed treatment. Measures were 24-hour ambulatory BP, lipid levels, weight, and psychological measures. RESULTS: Blood pressure was significantly reduced in the immediate treatment group and did not change in control subjects (-6.1 vs +0.9 mm Hg for systolic and -4.3 vs +0.0 mm Hg for diastolic pressure). When the wait list control group was later treated, BP was similarly reduced by -7.8 and -5.2 mm Hg, and for the combined sample, total change at follow-up was -10.8 and -8.5 mm Hg. Level of BP at the beginning of treatment was correlated with BP change (r = 0.45 [P<.001] and 0.51 [P<.001], respectively), and amount of systolic BP change was positively correlated with reduction in psychological stress (r = 0.34) and change in anger coping styles (r = 0.35-0.41). CONCLUSIONS: Individualized stress management is associated with ambulatory BP reduction. The effects were replicated and further improved by follow-up. Reductions in psychological stress and improved anger coping appear to mediate the reductions in BP change.

Cardiovascular recovery from acute laboratory stress: reliability and concurrent validity.

OBJECTIVE: We assessed the value of laboratory measures of cardiovascular recovery across four criteria: reliability across multiple tasks, reliability across a 3-year time interval, ability to predict daily ambulatory blood pressure, and interrelationships with coronary risk factors and psychosocial variables. METHODS: Three hundred twenty-nine healthy adults (mean age = 27.1 years) completed a two-part protocol consisting of 1 day of laboratory testing and 1 day of ambulatory monitoring. The laboratory protocol included a 15-minute baseline assessment followed by three 5-minute laboratory challenges (mental arithmetic, speech, and handgrip). Five-minute recovery periods followed each exercise. One hundred twenty-five participants returned after 3 years to repeat the protocol. RESULTS: When aggregated across tasks, cardiovascular recovery showed acceptable levels of internal consistency (alpha values = 0.7) and proved relatively stable across time (r values = 0.22-0.35). Recovery values statistically improved the prediction of daily ambulatory readings above baseline and stress reactivity laboratory values (p values < .001) but were largely unrelated to coronary risk factors or psychosocial measures. CONCLUSION: These results suggest that cardiovascular recovery from acute laboratory stress can be treated as a stable individual difference variable that can -improve standard laboratory-based predictor models of ambulatory readings.

Background estimation in experimental spectra

A general probabilistic technique for estimating background contributions to measured spectra is presented. A Bayesian model is used to capture the defining characteristics of the problem, namely, that the background is smoother than the signal. The signal is allowed to have positive and/or negative components. The background is represented in terms of a cubic spline basis. A variable degree of smoothness of the background is attained by allowing the number of knots and the knot positions to be adaptively chosen on the basis of the data. The fully Bayesian approach taken provides a natural way to handle knot adaptivity and allows uncertainties in the background to be estimated. Our technique is demonstrated on a particle induced x-ray emission spectrum from a geological sample and an Auger spectrum from iron, which contains signals with both positive and negative components.

Psychological response styles and cardiovascular health: confound or independent risk factor?

Using results from 2 large cardiovascular studies, the authors examined the utility of treating psychological response styles as confounds (e.g., factors undermining relationships with other self-report variables) versus distinct personality traits in the prediction of cardiovascular health. Study 1 consisted of a 3-year prospective study of ambulatory blood pressure levels in healthy adults (N = 125). Study 2 comprised a 12-week drug treatment program for ischemic heart disease patients (N = 95). Participants completed measures of psychological factors and self-deception and impression management in each study. Results consistently favored using response styles as direct predictors. Self-deception scores predicted elevated 3-year diastolic and systolic blood pressure changes in Study 1 and poorer treatment outcomes in Study 2. Statistically controlling for response style effects within the psychological factors generally did not improve predictions. These findings argue against the conceptualization of response styles as stylistic confounds.

Psychological treatments in cardiac rehabilitation: review of rationales and outcomes.

OBJECTIVE: In this review, the place of psychological interventions in cardiac rehabilitation and differences in underlying rationales are presented. Treatment approaches vary in that some practitioners favor biobehavioral approaches with strong relaxation/breathing components, whereas others offer unstructured support, psychoeducation to maximize compliance, or psychological interventions directed at reducing emotional distress. METHODS: The effectiveness of psychosocial rehabilitation for endpoints like mortality, recurrence, emotional distress, and intermediate hard endpoints is reviewed by integrating conclusions from narrative and meta-analytic reviews as well as recent major clinical trials. RESULTS: The aggregated findings support the use of psychosocial interventions and they also help to explain critical differences in outcome in that studies which fail to reduce distress also fail to lead to reduced mortality or reduced event recurrence. CONCLUSION: Gender differences in outcome and recent trends in cardiology are discussed because both have distinct consequences for the effective delivery of psychological services to cardiac patients.